Getting more fit might reduce the risk of death for elderly men with high blood pressure, a new study suggests.

Compared to the least-fit men, those who had the highest levels of fitness had nearly half the risk of death. For men in the low-fitness category, the risk of dying was 18 percent lower. And, men in the moderate-fitness category had a 36 percent lower death risk, according to the study.

A moderate "level of fitness is achievable by most elderly individuals engaging in a brisk walk of 20 to 40 minutes, most days of the week," lead author Dr. Charles Faselis, a professor of medicine at George Washington University in Washington, D.C., said in a news release from the journal Hypertension .

Researchers used a standard treadmill test to assess the fitness of more than 2,100 men, 70 and older, with high blood pressure. They were classified as being least-fit, low-fit, moderately-fit or high-fit. The men were followed for an average of nine years.

"For every 100 people who died in the least-fit category, 82 died in the low-fit category, 64 died in the moderate-fit and 52 died from the high-fit category," senior author Peter Kokkinos, a professor at Veterans Affairs Medical Center, Georgetown University School of Medicine and George Washington University School of Medicine and Health Sciences, said in the news release.

"The death rate is cut in half for those in the highest fitness category," he noted.

The study was published on May 12 online in Hypertension . Although the study found an association between a reduced risk of death and greater fitness, it wasn't designed to prove that increased exercise was the definitive cause of the lower death risk.